#include<iostream>
using namespace std;
int main()
{
	float a, b;
	char c;
	cin>>a>>b>>c;
	switch(c)
	{
		case '+' : cout<<a + b<<endl; break;
		case '-' : cout<<a - b<<endl; break;
		case '*' : cout<<a * b<<endl; break;
		case '/' : 
			if (b == 0)
			{
				cout<<"Divided by zero!"<<endl; 
			}
			else
			{
				cout<<a / b<<endl;
			}
			break;
		default :
			cout<<"Invalid operator!"<<endl; 
			break;
	}
	return 0;
} 
